International Association
for Cryptologic Research

Since the proposal of Bitcoin in 2008, the world has seen accelerated growth in the field of blockchain and discovered its potential to immensely transform most industries, one of the first and most important being finance. The blockchain trilemma states that blockchains can have security, scalability, and decentralization, but never all three at the same time, in the same amount. At the moment, the most successful blockchains have a lack of scalability that researchers and developers try to alleviate by solutions like layer 2s. Most of these solutions rely on cryptographic primitives and technologies, like collision-free hash function or zero-knowledge proofs. In this paper we explore a few of the most popular solutions available now, their improvements to scalability, their drawbacks and security risks.